Patent GB-743112-A (GB)
Title: Improved apparatus suitable for controlling the relationship between continuously travelling elements and devices periodically co-operating therewith
Inventor: GILBERT VICTOR HENRY
IPC: B26D1/60
Filed: 1950-11-03
Abstract: 743,112. Cutting paper tubes. ROBINSON, E. B. March 25, 1952 [Nov. 3, 1950; Feb. 13, 1951], Nos. 26936/50 and 3435/51. Class 31 (1). [Also in Groups XXVIII and XL (b)] Apparatus for controlling the relationship between a continuously-travelling element and a device periodically co-operating therewith, comprises control means operable by control marks or irregularities on the element, and electrical time-delay means (see Group XL (b)) which renders the control means ineffective for desired periods after each control period has commenced. As applied to apparatus for forming a paper strip into a tube and cutting the tube into lengths to form the bodies of containers each bearing a pattern, an impulse from a photo-electric device influenced by marks on the strip is applied to the grid of a thyratron valve whereupon a circuit is closed momentarily to control the relationship between the paper-feeding and cutting mechanisms according to the setting of a "selector" mechanism which detects whether the cut is early, late or in correct register. The control mechanism is reset after a delay depending on whether control is to be exercised by every mark, alternate or other desired marks. Cutting-apparatus.-Two banks of cutters 204, 205, Fig. 9, one on each side of a mandrel 219 extending from the mandrel 290, Fig. 1, on which the tube is formed, are supported on a carriage 201 reciprocated by a cam 358, the forward stroke comprising acceleration, constant speed and gradual deceleration. The cam acts through a lever 367 and an extensible link 368 connected to a lever 369 linked to the carriage, the point of connection being movable by means of a hand-operated worm gear, Fig. 4 (not shown), whereby the stroke of the carriage can be adjusted. The bank 204 is carried by a slide 207 moved into cutting position by cams 220 against the action of springs. The bank 205 is actuated from the bank 204 by an adjustable connection 245 ... 247. The cams 220 are fixed to a shaft 222 driven by gearing from the output shaft of a reduction gear, the input shaft being driven from the shaft 268 as described below; cutting can be suspended by turning a lever 256 to trip cam rollers 221. To avoid bending the mandrel during cutting, a roller, Fig. 10 (not shown), is lifted into a mandrel-supporting position by cam-blocks on the slide 207, and to prevent lateral displacement of the carriage 201 during its travel, a bar 359 is fixed thereto so as to ride between horizontal rollers 360 and 361. The mandrel 219 telescopes in the mandrel 290 and is rotated by gears and a belt 750 from the shaft 268 and moved longitudinally with the carriage by means of a rod 301. The machine may, alternatively be of the type wherein there is a variable pause between successive cutting cycles. The shaft 268 drives the input shaft of the reduction gear through a differential 500, a variable gear 476 and chain gearing 376, correction of the registration of the cut being applied to the differential by solenoids 392, 393, Fig. 8, acting on a rod 424 adapted to turn an eccentric 404 (Fig. 6) linked to a ball race 204 whereby a shaft 398 driven from a motor 395 is moved axially to bring either of two pairs of clutch discs 399, 406 and 401, 405 into engagement so as to drive one of the bevel gears 411, 412, and rotate a bevel 418 clockwise or anticlockwise, this rotation being applied to the planetary gears of the differential. To obtain a quicker correction, a switch is closed to start a motor 626 connected to the output shaft of the clutch; also, the eccentric 404 may be turned by an over-riding manual control lever 423. Selector switch.-Pairs of contacts 431,432, Fig. 20, are operated by a cam 430 driven from the output shaft of the reduction gearing. The contacts are carried by a table 434 fixed in angularly adjustable position by a screw 433. The pair of contacts 431 is carried by a segment 436 adjustable to vary the angular relationship between the two pairs and consequently the extent of the neutral zone. Specifications 653,613, 703,981 and 743,115, are referred to.